JP3492820B2 - Compound semiconductor single crystal manufacturing equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to ZnSe, CdTe and ZnS.
II-VI group such as InP, GaP, GaAs or the like, or a part of constituent elements such as a ternary compound thereof is dissociated at a high temperature, and a single crystal manufacturing apparatus for compound semiconductor is likely to evaporate. It is about.

[0002]

2. Description of the Related Art Liquid-encapsulated Czochralski method (L
EC method), horizontal Bridgman method (HB method), vertical Bridgman method (VB method), vertical temperature gradient solidification method (VGF method), etc. are used. Among them, the VB method and the VGF method have great expectations as industrial manufacturing methods because they can manufacture high-quality single crystals that are relatively large and have few dislocations.

By the way, when a specific component dissociates and evaporates, the composition of the completed single crystal shifts, and the desired single crystal cannot be obtained. Therefore, for example, Japanese Unexamined Patent Publication (Kokai) No. 5-70276 discloses a method of performing crystal growth by vacuum-sealing the entire crucible in an airtight container such as a quartz ampoule so that vapor of the dissociated component is not dissipated. ing. However, in this method, the quartz ampoule must be sealed and the quartz ampoule must be destroyed to take out the grown crystal for each crystal growth operation, which complicates the work and prevents the repeated use of the quartz ampoule. , The manufacturing cost becomes high.

On the other hand, Japanese Patent Laid-Open No. 3-247582 discloses that a high dissociation pressure component provided separately from a raw material for growing crystals in a crucible is vaporized in a closed type growth chamber to grow crystals in the crucible. A method for suppressing transpiration of a specific component from a raw material is disclosed. According to the method, as shown in FIG. 2, in a vertical temperature gradient furnace, a cap (hereinafter, referred to as an internal chamber) 62 is provided inside a heater 61 built in a furnace body, and a lower end portion of the internal chamber 62 is provided. Is immersed in a liquid sealant 64 consisting of B ₂ O ₃ housed in an annular groove around the lower part of the susceptor 63, thereby enclosing a crucible 65 supported on the susceptor 63 in the inner chamber 62. A mold growth chamber is formed. The high dissociation pressure component 66 is arranged inside the liquid sealant 64 in the susceptor 63.

In the above, after the crystal growth raw material (for example, CdTe polycrystal) in the crucible 65 is melted by energizing the heater 61, it is solidified from the lower end side of the raw material melt 67 to form the single crystal 68.
When growing, the high dissociation pressure component 66 (eg Cd) is also heated to generate Cd vapor, and the high dissociation pressure component 66 is heated so that the vapor pressure becomes equal to the equilibrium dissociation pressure of the raw material melt 67. The temperature is controlled independently of the heating of the raw material. Thereby, the evaporation of the high dissociation pressure component in the raw material melt 67 is suppressed, and the single crystal is grown in a state where the change in the melt composition is suppressed.

Further, in the above structure, when the liquid sealant 64 is melted at a relatively low temperature, the susceptor 63 is moved up and down by the lower shaft 69 to switch the growth chamber between the closed state and the open state. Therefore, the workability is improved and the internal chamber 62 is repeatedly used to form a closed chamber.

[0007]

However, in the configuration described in Japanese Patent Laid-Open No. 3-247582 described above, the vapor generated by the high dissociation pressure component 66 disposed below the crucible 65 does not allow a closed type growth chamber. It is difficult to maintain the entire vapor pressure at a predetermined vapor pressure, and therefore, there is a problem that evaporation from the raw material melt 67 in the crucible 65 cannot be sufficiently suppressed.

That is, during the above single crystal growth operation, the inside of the furnace is previously replaced with an atmosphere of an inert gas such as argon gas. When the vapor having a high dissociation pressure component is heavier than such an inert gas, it is difficult for the vapor generated below to diffuse upward quickly. Particularly, in the configuration described in the above publication, when the internal pressure of the internal chamber 62 increases due to the pressure of the steam generated by heating the high dissociation pressure component 66,
The liquid surface of the liquid sealant 64 changes to create a gap, and the vapor generated from the high dissociation pressure component 66 immediately leaks out of the internal chamber 62 through the gap. Therefore, it is difficult to maintain the surroundings of the crucible 65 located on the upper side in a predetermined vapor pressure atmosphere, and as a result, evaporation from the raw material melt 67 occurs,
The compositional deviation cannot be sufficiently suppressed.

Further, in the above, there is also a problem that the steam generated from the high dissociation pressure component 66 leaks out of the internal chamber 62, so that the steam adheres to, for example, the heater 61 and pollutes the inside of the furnace. ing. On the other hand, for example, in the process of finishing the growth of the single crystal and cooling it, unless the portion of the liquid sealant 64 is specially heated, the liquid sealant 64 will be solidified when it becomes the freezing point or less (B 500 ° C for ₂ O ₃
Below), in extreme cases, it will be in the same state as when brazing. Therefore, when switching between the closed state and the open state of the growth chamber by operating the lower shaft 69, it is necessary to monitor the temperature state sufficiently,
There is also a problem that workability cannot always be improved sufficiently.

The present invention has been made in view of the above-mentioned conventional problems. It is possible to suppress the change in the composition of the crystal growth raw material and manufacture a high quality single crystal, and further,
It is an object of the present invention to provide a compound semiconductor single crystal production apparatus capable of preventing contamination in a furnace and improving workability.

[0011]

In order to achieve the above object, the apparatus for producing a single crystal of a compound semiconductor according to claim 1 of the present invention comprises a furnace body filled with an inert gas and a furnace body. The main heating means, the raw material storage container which stores the raw material for growing the single crystal and is arranged in the heating region by the main heating means, and the high dissociation pressure component which is arranged below the raw material storage container. A single crystal growth apparatus for a compound semiconductor, comprising: a reservoir; an auxiliary heating means for heating the reservoir; and an airtight chamber that surrounds a raw material storage container and a reservoir inside the main heating means, wherein the airtight chamber has a substantially inverted cross section. One is a U-shaped tubular body, and a communication path for communicating the inside and the outside of the airtight chamber is formed in a portion of the lower end of the airtight chamber, which is maintained at a temperature lower than the melting point of the high dissociation pressure component. Airtight chamber, is characterized in that steam guide means having a high dissociation pressure component of the vapor generated in the reservoir to feed the container around the guide path for guiding upward.

According to the above construction, the vapor of the high dissociation pressure component generated from the reservoir below the raw material container is guided upward by the vapor guide means. Therefore, even when the vapor of the high dissociation pressure component is heavier than the inert gas, the vapor is more reliably supplied to the surroundings of the raw material storage container, and the vapor pressure around that is
It quickly follows the vapor pressure around the reservoir according to the reservoir heating temperature by the sub-heating means. As a result, evaporation from the raw material melt in the raw material storage container heated by the main heating means is suppressed, and as a result, a good quality single crystal having an intended composition can be grown.

On the other hand, after the vapor generated in the reservoir is once guided around the raw material storage container, a downward diffusive flow is generated toward the communication passage on the lower end side of the airtight chamber. Is in a temperature state lower than the melting point of the high dissociation pressure component, the vapor is deposited as droplets, which suppresses the outflow to the outside of the airtight chamber. As a result, vapor does not adhere to other internal furnace structures such as the main heating means outside the airtight chamber, and in-furnace contamination is prevented.

Further, the airtight chamber is a tubular body having a substantially inverted U-shaped cross section, and therefore, when the vertical movement is carried out, a position for enclosing the raw material storage container and the reservoir inside the main heating means and an open position are provided. Can be easily switched.
As a result, it is possible to use it repeatedly, and it is possible to easily perform the setting operation and the taking-out operation of the raw material storage container or the reservoir, so that the workability is improved.

According to a second aspect of the present invention, in the apparatus for producing a single crystal of a compound semiconductor according to the first aspect, the reservoir is formed in an annular shape substantially along the outer peripheral shape of the raw material container.
The vapor guide means is characterized by comprising an inner sleeve and an outer sleeve each having a lower end fitted to the inner and outer surfaces of the reservoir and extending upward. According to this configuration, the vapor of the high dissociation pressure component is supplied substantially uniformly from the annular reservoir through the guide passage between the cylindrical inner sleeve and the outer sleeve over the entire outer circumference of the raw material storage container. . Therefore, even if the vapor flows downward from the guide passage, a predetermined vapor atmosphere can be secured throughout the raw material storage container, so that evaporation from the raw material melt can be more reliably suppressed. can do.

According to a third aspect of the present invention, in the apparatus for producing a single crystal of a compound semiconductor according to the second aspect, the raw material storage container comprises a crucible having an opening at the upper end, and each of the upper ends of the inner sleeve and the outer sleeve is a furnace. It is characterized in that it is set at a height position higher than the upper end of the crucible set in the body. According to this configuration, the vapor of the high dissociation pressure component from the reservoir is guided through the guide path between the inner sleeve and the outer sleeve to a position higher than the open upper end surface of the crucible, and therefore, is easily crucible. Flows into the crucible through the top opening of the. As a result, the atmosphere on the surface of the raw material melt in the crucible is quickly maintained at a predetermined vapor pressure, so that evaporation from the raw material melt is more reliably suppressed.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described with reference to FIG. FIG. 1 shows an apparatus for producing a single crystal by the vertical Bridgman method, which comprises a high-pressure vessel 1 as a furnace body having a pressure resistant structure, and the high-pressure vessel 1 has a cylindrical body 2 and An upper lid 3 that covers the upper end opening of the body portion 2, a ring-shaped lid 4 that is fitted to the lower end opening of the body portion 2, and an inner lid that is fitted from below to close the central opening of the ring-shaped lid 4. It is composed of a lower lid 5. Body 2
The upper lid 3 and the ring-shaped lid 4 are sealed by the seal rings 6a and 6b, and the ring-shaped lid 4 and the inner lower lid 5 are the seal rings 6c.
Are hermetically sealed by each. The upper lid 3 is provided with a gas supply / discharge path 7 for pressurizing and injecting an inert gas such as argon gas into the high-pressure container 1.

Inside the high-pressure vessel 1, a main heater (main heating means) 8 and a sub-heater (sub-heating means) 9 are arranged. The main heater 8 is configured by arranging a plurality of cylindrical heater elements 8a to 8d side by side in a vertical direction (four stages in the figure), and on the lower side thereof, a cylindrical shape similar to the above is formed. A sub-heater 9 composed of heater elements 9a and 9b in stages is arranged. The heater elements 8a to 8d, 9a and 9b are controlled in power supply so that the temperature detected by a temperature detector (not shown) provided in each step is maintained at their set temperature.

Outside the main heater 8 and the sub-heater 9, a cylindrical heat insulating structure 11 is provided along the inner wall surface of the high-pressure container 1 with its upper surface closed in an inverted cup shape. The heat insulating structure 11 is composed of a gas impermeable layer and a heat insulating material. As will be described later, in the course of the crystal growth operation, the heaters 8 and 9 are energized while the high-pressure vessel 1 is filled with the high-pressure inert gas. At this time, the high-pressure vessel 1 also contains high-pressure gas. Although the heat is heated by the heaters 8 and 9 and violent convection occurs, excessive heat dissipation to the high-pressure vessel 1 due to this flow is suppressed by the heat insulating structure 11. As a result, overheating of the high-pressure container 1 is prevented, and a more stable heating area is formed inside the heaters 8 and 9.

On the other hand, a cylindrical crucible support 12 extending vertically through the center of the inner lower lid 5 is airtight and movable up and down with respect to the inner lower lid 5 by a seal ring 13. It is provided in. And this crucible support 12
A crucible 14 as a raw material storage container for storing a raw material for growing a single crystal is supported in an upright state. This crucible is made of, for example, p-BN, and has a thin tube-shaped seed well 14a at the lower end portion into which a rod-shaped seed crystal 24 described later is inserted. The upper part thereof is formed into a circular tube having an inner diameter of about 1 inch via a tapered portion 14b, and the outer diameter thereof is slightly smaller than the outer diameter of the crucible support base 12.

Further, in the high-pressure container 1, the crucible 14 described above is provided.
An airtight chamber 15 having a substantially inverted U-shaped cross section, which surrounds the crucible support 12 and the crucible support 12 inside the main heater 8 and the sub-heater 9,
It is arranged in a state of being placed on the inner lower lid 5. The material of the airtight chamber 15 is selected from the viewpoint of heat resistance, airtightness, and avoidance of contamination, and is made of glassy carbon in this embodiment. Materials other than glassy carbon include p-BN and Si as materials satisfying the above requirements at a temperature higher than the melting point of the single crystal growth material (for example, 1520 ° C for ZnSe and 1830 ° C for ZnS).
Examples include ceramics such as C, pyrolytic graphite, glassy carbon, graphite that has undergone a special treatment such as graphite that is airtightly coated with pyrolytic graphite, or refractory metals such as molybdenum, tantalum, and tungsten, and their alloys. .

In the airtight chamber 15, a communication passage 16 penetrating the side wall surface in the form of a fine hole is formed on the bottom side close to the inner lower lid 5. Airtight chamber 15 through this communication passage 16
The interior and exterior spaces of the chamber communicate with each other, which allows
15 Generation of differential pressure between inside and outside is suppressed. The communication passage 16 may be formed by, for example, partially cutting out the lower end of the airtight chamber 15 and forming a gap between the airtight chamber 15 and the inner lower lid 5.

The crucible support 12 extending vertically up and down substantially in the center of the airtight chamber 15 is moved up and down by an elevator device (not shown) provided outside the high pressure container 1,
As a result, the crucible 14 is also configured to move up and down in the heating region in the airtight chamber 15 by the main heater 8. In the airtight chamber 15, an annular reservoir 17 is further arranged between the crucible support 12 and the airtight chamber 15 on the bottom side thereof. This reservoir
The section 17 is formed in a substantially U shape having a recessed groove from the upper surface, and the high dissociation pressure component 18 is accommodated in the recessed groove. The reservoir 17 is arranged at a height position corresponding to the sub heater 9 by a support stand (not shown) placed on the inner lower lid 5.

On the inner and outer circumferences of the reservoir 17, there are provided a cylindrical inner sleeve 19 and outer sleeve 20 for extending the inner wall surface and the outer wall surface, respectively. A guide passage 21 is formed to guide the vapor generated by heating the high dissociation pressure component 18 in 17 upward. Both of these sleeves 19 and 20 are
The inner and outer wall surfaces of 17 are welded together so as to ensure airtightness. When using a material that cannot be welded, use a suitable sealant, etc.
It is also possible to adopt a configuration in which it is connected to the inner and outer wall surfaces of.

The lengths of the sleeves 19 and 20 in the vertical direction are set so that the upper end position thereof substantially coincides with the height position of the upper end surface of the crucible 14 when it is located at the uppermost position as shown in the figure. Has been done. In addition, the inner diameter of the inner sleeve 19 is set so that the inner gap 22 between the inner sleeve 19 and the crucible support 12 is as small as possible within a range that does not hinder the vertical movement of the crucible support 12. The outer shape is set so that the outer gap 23 between the airtight chamber 15 and the outer sleeve 20 is as small as possible within a range that does not hinder the work for fitting the airtight chamber 15 onto the outer sleeve 20.

Next, an operation procedure when a ZnSe single crystal is manufactured using the above apparatus and an example of the result will be described. First, the seed well 14a of the crucible 14 was fitted with a ZnSe seed crystal 24 having a diameter of 2 mm and a length of 30 mm, which was produced by the vapor phase epitaxy method, and then the crucible 14 was filled with 6N grade ZnSe.
200 g of polycrystal was filled as a raw material for crystal growth. On the other hand, the reservoir 17 was filled with 30 g of Zn as the high dissociation pressure component 18.

Then, the inner lower lid 5 of the high-pressure container 1 was lowered together with the crucible support base 12, the crucible 14 was set on the crucible support base 12, and the reservoir 17 was set on the inner lower lid 5. Next, after mounting the airtight chamber 15 on the inner lower lid 5, the inner lower lid 5 was raised together with the crucible support 12 to set the inside of the furnace as shown in the figure, and the high pressure vessel 1 was sealed.

After the above preparatory work was completed, the inside of the high-pressure vessel 1 was evacuated through the gas supply / exhaust passage 7, and then the gas replacement operation of filling and discharging argon gas at 10 kgf / cm ² was performed twice. . Next, use argon gas at 5 kgf / cm
² filled. In the course of such a gas replacement operation, gas is exhausted and sent through the communication passage 16 in the airtight chamber 15, and the inner sleeve 19 and the outer sleeve 20 are provided around the crucible 14. Gas is exhausted and sent through the inner gap 22 and the outer gap 23.

After that, energization of the main heater 8 is started, and the upper side of the crucible 14 is heated to 1550 ° C. at a temperature rising rate of 500 ° C./hr.
The raw material was melted by raising the temperature until. At this time, the electric power supplied to each heater element 8a to 8d is controlled so that each set temperature is maintained for each zone corresponding to each heater element 8a to 8d of the main heating heater 8, and the seed crystal 24 From the portion, the temperature distribution is such that the temperature decreases downward. Then, at approximately the central position of the seed crystal 24, that is, at a distance of about 15 mm from the lower end, the melting point of ZnSe is 1520.
The temperature was controlled to be 0 ° C., whereby the upper end side of the seed crystal 24 was also partially melted and seeding was performed on the raw material melt 25 above it.

The pressure in the high-pressure vessel 1 is 10 kgf / cm when the upper side of the crucible 14 is heated to 1550 ° C. as described above.
^The temperature was adjusted so that it would be ² . On the other hand, while the heating by the main heater 8 is started to raise the temperature of the raw material, at the same time, the energization of the sub-heater 9 is also started to heat the high dissociation pressure component 18 contained in the reservoir 17 to thereby generate the Zn vapor. Was generated. And the Zn vapor pressure generated in this reservoir 17 is about
The heating temperature of the reservoir 17 by the sub-heater 9 was controlled to 1000 ° C. so as to be 2.4 kgf / cm ² .

After seeding as described above, crucible support base
The lowering operation of 12 was started, and the crucible 14 was lowered at a speed of 3 mm / hr to a position where the upper end of the crucible 14 was 1400 ° C. or lower. In the process of this operation, the raw material melt 25 in the crucible 14 gradually solidifies upward from the lower side in contact with the seed crystal 24, and the entire raw material melt 25 grows as a single crystal 26. In this way, after solidifying the entire amount of the raw material melt 25 in the crucible 14,
After cooling at 100 ° C./hr, argon gas was released from the inside of the high pressure vessel 1 to return to atmospheric pressure. Then, the inner lower lid 5 was lowered to open the high-pressure container 1, the airtight chamber 15 was removed, and the crucible 14 was recovered.

At this time, the reservoir 17 in the airtight chamber 15
Zn was deposited in droplets on the portion, but the other portions were clean inside and outside the airtight chamber 15. ZnSe taken out from the crucible 14 is a clear yellow transparent, and about 70% from the bottom does not contain twin crystals, and the resistance value is a low resistance of about 10 ^-2 Ωcm, which is a very high quality single crystal. there were.

As described above, in this embodiment, while Zn vapor is generated in the reservoir 17 below the crucible 14, the ZnSe raw material in the crucible 14 is melted and solidified to grow a single crystal. Let At this time, the high-pressure container 1 is filled with argon gas in advance, and the Zn vapor is heavier than the argon gas. Therefore, if the inner sleeve 19 and the outer sleeve 20 in the present embodiment are not provided, the Zn vapor generated in the reservoir 17 rises due to diffusion in the argon gas and reaches the periphery of the crucible 14,
The main flow is a flow that flows downward through a gap between the reservoir 17 and, for example, the crucible support 12, and diffuses toward the communication passage 16 of the airtight chamber 15. Therefore, the crucible 14 is not supplied with sufficient Zn vapor that reaches a vapor pressure that can suppress evaporation of Zn from the raw material melt, and as a result,
Zn evaporates from the raw material melt 25 to cause compositional deviation.

Therefore, in the present embodiment, in order to guide the Zn vapor generated in the reservoir 17 to the height position of the crucible 14 above it, vapor guide means consisting of the inner sleeve 19 and the outer sleeve 20 is provided. . As a result, the Zn vapor does not leak downward before reaching the height position of the crucible 14 and is reliably guided to the height position of the crucible 14, so the Zn vapor pressure around the crucible 14 also comes from the reservoir 17. The supplied Zn vapor maintains the pressure at which the evaporation of Zn from the raw material melt 25 can be suppressed. As a result, the composition of the raw material melt 25 does not shift, and the single crystal 26 having the intended composition can be grown.

Further, in the above embodiment, the inner gap 22 between the inner sleeve 19 and the crucible support 12 and the outer gap between the outer sleeve 20 and the airtight chamber 15 are formed.
Since each of the 23 is set to be as small as possible, the amount of Zn vapor that is once guided from the reservoir 17 upward and then flows downward through the gaps 22 and 23 is as small as possible. Therefore, the high dissociation pressure component stored in the reservoir 17
Since the amount of 18 can be made smaller, the production efficiency is improved.

In addition, it flows downward through the gaps 22 and 23.
Even if the amount of Zn vapor increases with time, this becomes a flow toward the communication passage 16 formed in the hermetic chamber 15. The communication passage 16 is formed on the lower end side of the airtight chamber 15 away from the main heater 8 and the sub-heater 9, and this portion is a portion kept at a temperature lower than the melting point of Zn 419.5 ° C. is there. Therefore, Zn vapor is deposited while reaching this site. As a result, since the Zn vapor does not flow out of the airtight chamber 15, the Zn vapor does not adhere to the main heating heater 8 and the sub-heating heater 9 and the power supply members for these heaters, and the inside of the furnace is contaminated. Is prevented.

On the other hand, in the above embodiment, the reservoir 17 is formed in an annular shape coaxially arranged with the crucible 14, and from this reservoir 17, through the guide passage 21 between the inner sleeve 19 and the outer sleeve 20, Zn vapor is supplied all around the upper end surface of the crucible 14. For this reason, a predetermined vapor atmosphere is quickly formed over the entire crucible 14.

Further, in the above embodiment, the inner sleeve 19
The vertical lengths of the outer sleeve 20 and the outer sleeve 20 are the crucible 14 with the upper end position set in the high-pressure container 1.
It is set so as to substantially coincide with the height position of the upper end face of the. As a result, the Zn vapor generated in the reservoir 17 is guided to the upper surface opening position of the crucible 14 and therefore easily flows into the crucible 14 through the upper end opening of the crucible 14. As a result, since the atmosphere on the surface of the raw material melt 25 in the crucible 14 is quickly maintained at a predetermined vapor pressure, the raw material melt 25
Evaporation from 25 is reliably suppressed.

The above embodiment is not intended to limit the present invention, and various modifications can be made within the scope of the present invention. For example, each of the sleeves 19 and 20 described above can be configured so as to be elongated further upward. On the other hand, for example, crucible
When 14 is made of a gas permeable material, it is not necessary to guide the Zn vapor to the height of the upper end opening position of the crucible 14, and for example, at the height position of the crucible 14 near the seed well 14a, the sleeves 19 and 20 are provided. It is also possible to adopt a configuration in which the upper end of is located.

On the other hand, in the above embodiment, the sub-heater 9 for heating the reservoir 17 is provided outside the airtight chamber 15 in the same manner as the main heater 8, but the sub-heater 9 and the temperature measurement of the thermocouple, etc. The member may be provided inside the airtight chamber 15. Further, in the above embodiment, the production of ZnSe single crystal was described as an example, but in addition, CdTe or Zn
Production of compound semiconductor single crystal in which a part of constituent elements such as II-VI group such as S, III-V group such as InP, GaP, GaAs, etc., or ternary compounds thereof are easily dissociated at high temperature The present invention can be applied to. Further, the present invention is not limited to the apparatus of the vertical Bridgman method (VB method) described above, but can be applied to an apparatus of the vertical temperature gradient solidification method (VGF method).

[0041]

As described above, according to the first aspect of the present invention.
In the apparatus described, the vapor of the high dissociation pressure component generated from the reservoir below the raw material storage container is more reliably supplied to the surroundings of the raw material storage container even when this is heavier than the inert gas, and the vapor pressure around the raw material storage container is set to a predetermined value. The pressure can be stably maintained. As a result, evaporation from the raw material melt in the raw material storage container is suppressed, and it becomes possible to grow a good quality single crystal having an intended composition.

Further, the vapor, which is once introduced to the periphery of the raw material storage container and then causes a downward diffusive flow toward the communication passage on the lower end side of the airtight chamber, is deposited as droplets at the portion of the communication passage. Thereby, the outflow to the outside of the airtight chamber is suppressed. As a result, vapor does not adhere to other internal furnace structures such as the main heating means outside the airtight chamber, and in-furnace contamination is prevented.

Further, the airtight chamber can be easily switched between a position in which the raw material container and the reservoir are enclosed inside the main heating means and an open position by an operation of moving the airtight chamber up and down. As a result, it is possible to use it repeatedly, and it is possible to easily perform the setting operation and the taking-out operation of the raw material storage container or the reservoir, so that the workability is improved. In the apparatus according to the second aspect, since the vapor of the high dissociation pressure component is supplied from the annular reservoir almost uniformly over the entire outer periphery of the raw material storage container, a predetermined vapor atmosphere is provided over the entire raw material storage container. Can be secured. As a result, evaporation from the raw material melt can be more reliably suppressed, and a high-quality single crystal with no compositional deviation can be manufactured.

In the apparatus according to the third aspect, the vapor of the high dissociation pressure component from the reservoir flows into the crucible through the upper opening of the crucible, whereby the atmosphere on the surface of the raw material melt in the crucible has a predetermined vapor content. Holds quickly with pressure.
As a result, evaporation from the raw material melt can be more reliably suppressed, and a high-quality single crystal with no composition deviation can be manufactured.

[Brief description of drawings]

FIG. 1 is a schematic vertical cross-sectional view showing the configuration of a compound semiconductor single crystal manufacturing apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic vertical cross-sectional view showing a configuration of a main part of a conventional single crystal manufacturing apparatus.

[Explanation of symbols]

1 High-pressure container (furnace body) 8 Main heating heater (main heating means) 9 Sub-heater (sub-heating means) 14 Crucible (raw material storage container) 15 airtight chamber 16 passages 17 Reservoir 18 High dissociation pressure component 19 Inner sleeve (steam guide) 20 Outer sleeve (steam guide) 21 guideway

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-214089 (JP, A) JP-A-5-97564 (JP, A) JP-A-5-70276 (JP, A) JP-A-3- 247582 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) C30B 1/00-35/00

Claims (3)

(57) [Claims] 1. A furnace body filled with an inert gas, a main heating means arranged in the furnace body, and a raw material container for containing a raw material for growing a single crystal and arranged in a heating region by the main heating means. A reservoir that accommodates the high dissociation pressure component and that is arranged below the raw material storage container; a sub-heating unit that heats the reservoir; and an airtight chamber that surrounds the raw material storage container and the reservoir inside the main heating unit. An apparatus for producing a single crystal of a compound semiconductor, comprising: the airtight chamber comprises a cylindrical body having a substantially inverted U-shaped cross section, and a communication path for communicating the inside and the outside of the airtight chamber with each other at the lower end side of the airtight chamber. It is formed in a part that is kept at a temperature lower than the melting point of the pressure component, and in the airtight chamber, it guides the vapor of the high dissociation pressure component generated in the reservoir upwards to the periphery of the raw material storage container. Compound semiconductor single crystal manufacturing apparatus characterized by vapor guide means having a guide passage is provided. 2. The reservoir is formed in an annular shape substantially along the outer peripheral shape of the raw material storage container, and the vapor guiding means has a cylindrical inner sleeve and an outer side, the lower ends of which are fitted to the inner and outer surfaces of the reservoir and extending upward. The device for producing a single crystal of a compound semiconductor according to claim 1, wherein the device comprises a sleeve. 3. The raw material storage container comprises a crucible having an open upper end, and the upper ends of the inner sleeve and the outer sleeve are set so as to be located at a height position higher than the upper end of the crucible set in the furnace body. The apparatus for producing a single crystal of a compound semiconductor according to claim 2, wherein: